[linux-block.git] / drivers / hwspinlock / sprd_hwspinlock.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Spreadtrum hardware spinlock driver
 * Copyright (C) 2017 Spreadtrum  - http://www.spreadtrum.com
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/hwspinlock.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>

#include "hwspinlock_internal.h"

/* hwspinlock registers definition */
#define HWSPINLOCK_RECCTRL		0x4
#define HWSPINLOCK_MASTERID(_X_)	(0x80 + 0x4 * (_X_))
#define HWSPINLOCK_TOKEN(_X_)		(0x800 + 0x4 * (_X_))

/* unlocked value */
#define HWSPINLOCK_NOTTAKEN		0x55aa10c5
/* bits definition of RECCTRL reg */
#define HWSPINLOCK_USER_BITS		0x1

/* hwspinlock number */
#define SPRD_HWLOCKS_NUM		32

struct sprd_hwspinlock_dev {
	void __iomem *base;
	struct clk *clk;
	struct hwspinlock_device bank;
};

/* try to lock the hardware spinlock */
static int sprd_hwspinlock_trylock(struct hwspinlock *lock)
{
	struct sprd_hwspinlock_dev *sprd_hwlock =
		dev_get_drvdata(lock->bank->dev);
	void __iomem *addr = lock->priv;
	int user_id, lock_id;

	if (!readl(addr))
		return 1;

	lock_id = hwlock_to_id(lock);
	/* get the hardware spinlock master/user id */
	user_id = readl(sprd_hwlock->base + HWSPINLOCK_MASTERID(lock_id));
	dev_warn(sprd_hwlock->bank.dev,
		 "hwspinlock [%d] lock failed and master/user id = %d!\n",
		 lock_id, user_id);
	return 0;
}

/* unlock the hardware spinlock */
static void sprd_hwspinlock_unlock(struct hwspinlock *lock)
{
	void __iomem *lock_addr = lock->priv;

	writel(HWSPINLOCK_NOTTAKEN, lock_addr);
}

/* The specs recommended below number as the retry delay time */
static void sprd_hwspinlock_relax(struct hwspinlock *lock)
{
	ndelay(10);
}

static const struct hwspinlock_ops sprd_hwspinlock_ops = {
	.trylock = sprd_hwspinlock_trylock,
	.unlock = sprd_hwspinlock_unlock,
	.relax = sprd_hwspinlock_relax,
};

static void sprd_hwspinlock_disable(void *data)
{
	struct sprd_hwspinlock_dev *sprd_hwlock = data;

	clk_disable_unprepare(sprd_hwlock->clk);
}

static int sprd_hwspinlock_probe(struct platform_device *pdev)
{
	struct sprd_hwspinlock_dev *sprd_hwlock;
	struct hwspinlock *lock;
	int i, ret;

	if (!pdev->dev.of_node)
		return -ENODEV;

	sprd_hwlock = devm_kzalloc(&pdev->dev,
				   sizeof(struct sprd_hwspinlock_dev) +
				   SPRD_HWLOCKS_NUM * sizeof(*lock),
				   GFP_KERNEL);
	if (!sprd_hwlock)
		return -ENOMEM;

	sprd_hwlock->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(sprd_hwlock->base))
		return PTR_ERR(sprd_hwlock->base);

	sprd_hwlock->clk = devm_clk_get(&pdev->dev, "enable");
	if (IS_ERR(sprd_hwlock->clk)) {
		dev_err(&pdev->dev, "get hwspinlock clock failed!\n");
		return PTR_ERR(sprd_hwlock->clk);
	}

	ret = clk_prepare_enable(sprd_hwlock->clk);
	if (ret)
		return ret;

	ret = devm_add_action_or_reset(&pdev->dev, sprd_hwspinlock_disable,
				       sprd_hwlock);
	if (ret) {
		dev_err(&pdev->dev,
			"Failed to add hwspinlock disable action\n");
		return ret;
	}

	/* set the hwspinlock to record user id to identify subsystems */
	writel(HWSPINLOCK_USER_BITS, sprd_hwlock->base + HWSPINLOCK_RECCTRL);

	for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {
		lock = &sprd_hwlock->bank.lock[i];
		lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);
	}

	platform_set_drvdata(pdev, sprd_hwlock);

	return devm_hwspin_lock_register(&pdev->dev, &sprd_hwlock->bank,
					 &sprd_hwspinlock_ops, 0,
					 SPRD_HWLOCKS_NUM);
}

static const struct of_device_id sprd_hwspinlock_of_match[] = {
	{ .compatible = "sprd,hwspinlock-r3p0", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sprd_hwspinlock_of_match);

static struct platform_driver sprd_hwspinlock_driver = {
	.probe = sprd_hwspinlock_probe,
	.driver = {
		.name = "sprd_hwspinlock",
		.of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
	},
};

static int __init sprd_hwspinlock_init(void)
{
	return platform_driver_register(&sprd_hwspinlock_driver);
}
postcore_initcall(sprd_hwspinlock_init);

static void __exit sprd_hwspinlock_exit(void)
{
	platform_driver_unregister(&sprd_hwspinlock_driver);
}
module_exit(sprd_hwspinlock_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");
MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");
MODULE_AUTHOR("Long Cheng <aiden.cheng@spreadtrum.com>");
Commit	Line	Data
0c3e890b	1	// SPDX-License-Identifier: GPL-2.0
d8c8bbbb BW	2	/*
	3	* Spreadtrum hardware spinlock driver
	4	* Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
d8c8bbbb BW	5	*/
d8c8bbbb BW	6
d8c8bbbb BW	7	#include <linux/clk.h>
	8	#include <linux/delay.h>
	9	#include <linux/device.h>
	10	#include <linux/hwspinlock.h>
	11	#include <linux/io.h>
	12	#include <linux/kernel.h>
	13	#include <linux/module.h>
	14	#include <linux/of.h>
	15	#include <linux/of_device.h>
	16	#include <linux/platform_device.h>
d8c8bbbb BW	17
	18	#include "hwspinlock_internal.h"
	19
	20	/* hwspinlock registers definition */
	21	#define HWSPINLOCK_RECCTRL 0x4
	22	#define HWSPINLOCK_MASTERID(_X_) (0x80 + 0x4 * (_X_))
	23	#define HWSPINLOCK_TOKEN(_X_) (0x800 + 0x4 * (_X_))
	24
	25	/* unlocked value */
	26	#define HWSPINLOCK_NOTTAKEN 0x55aa10c5
	27	/* bits definition of RECCTRL reg */
	28	#define HWSPINLOCK_USER_BITS 0x1
	29
	30	/* hwspinlock number */
	31	#define SPRD_HWLOCKS_NUM 32
	32
	33	struct sprd_hwspinlock_dev {
	34	void __iomem *base;
	35	struct clk *clk;
	36	struct hwspinlock_device bank;
	37	};
	38
	39	/* try to lock the hardware spinlock */
	40	static int sprd_hwspinlock_trylock(struct hwspinlock *lock)
	41	{
	42	struct sprd_hwspinlock_dev *sprd_hwlock =
	43	dev_get_drvdata(lock->bank->dev);
	44	void __iomem *addr = lock->priv;
	45	int user_id, lock_id;
	46
	47	if (!readl(addr))
	48	return 1;
	49
	50	lock_id = hwlock_to_id(lock);
	51	/* get the hardware spinlock master/user id */
	52	user_id = readl(sprd_hwlock->base + HWSPINLOCK_MASTERID(lock_id));
	53	dev_warn(sprd_hwlock->bank.dev,
	54	"hwspinlock [%d] lock failed and master/user id = %d!\n",
	55	lock_id, user_id);
	56	return 0;
	57	}
	58
	59	/* unlock the hardware spinlock */
	60	static void sprd_hwspinlock_unlock(struct hwspinlock *lock)
	61	{
	62	void __iomem *lock_addr = lock->priv;
	63
	64	writel(HWSPINLOCK_NOTTAKEN, lock_addr);
	65	}
	66
	67	/* The specs recommended below number as the retry delay time */
	68	static void sprd_hwspinlock_relax(struct hwspinlock *lock)
	69	{
	70	ndelay(10);
	71	}
	72
	73	static const struct hwspinlock_ops sprd_hwspinlock_ops = {
	74	.trylock = sprd_hwspinlock_trylock,
	75	.unlock = sprd_hwspinlock_unlock,
	76	.relax = sprd_hwspinlock_relax,
	77	};
	78
b4d64193 BW	79	static void sprd_hwspinlock_disable(void *data)
	80	{
	81	struct sprd_hwspinlock_dev *sprd_hwlock = data;
	82
	83	clk_disable_unprepare(sprd_hwlock->clk);
	84	}
	85
d8c8bbbb BW	86	static int sprd_hwspinlock_probe(struct platform_device *pdev)
	87	{
	88	struct sprd_hwspinlock_dev *sprd_hwlock;
	89	struct hwspinlock *lock;
d8c8bbbb BW	90	int i, ret;
	91
	92	if (!pdev->dev.of_node)
	93	return -ENODEV;
	94
	95	sprd_hwlock = devm_kzalloc(&pdev->dev,
	96	sizeof(struct sprd_hwspinlock_dev) +
	97	SPRD_HWLOCKS_NUM * sizeof(*lock),
	98	GFP_KERNEL);
	99	if (!sprd_hwlock)
	100	return -ENOMEM;
	101
74cfa956	102	sprd_hwlock->base = devm_platform_ioremap_resource(pdev, 0);
d8c8bbbb BW	103	if (IS_ERR(sprd_hwlock->base))
	104	return PTR_ERR(sprd_hwlock->base);
	105
	106	sprd_hwlock->clk = devm_clk_get(&pdev->dev, "enable");
	107	if (IS_ERR(sprd_hwlock->clk)) {
	108	dev_err(&pdev->dev, "get hwspinlock clock failed!\n");
	109	return PTR_ERR(sprd_hwlock->clk);
	110	}
	111
3070c416 BW	112	ret = clk_prepare_enable(sprd_hwlock->clk);
	113	if (ret)
	114	return ret;
d8c8bbbb	115
b4d64193 BW	116	ret = devm_add_action_or_reset(&pdev->dev, sprd_hwspinlock_disable,
	117	sprd_hwlock);
	118	if (ret) {
	119	dev_err(&pdev->dev,
	120	"Failed to add hwspinlock disable action\n");
	121	return ret;
	122	}
	123
d8c8bbbb BW	124	/* set the hwspinlock to record user id to identify subsystems */
	125	writel(HWSPINLOCK_USER_BITS, sprd_hwlock->base + HWSPINLOCK_RECCTRL);
	126
	127	for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {
	128	lock = &sprd_hwlock->bank.lock[i];
	129	lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);
	130	}
	131
	132	platform_set_drvdata(pdev, sprd_hwlock);
d8c8bbbb	133
4d0c1c57 BW	134	return devm_hwspin_lock_register(&pdev->dev, &sprd_hwlock->bank,
	135	&sprd_hwspinlock_ops, 0,
	136	SPRD_HWLOCKS_NUM);
d8c8bbbb BW	137	}
	138
	139	static const struct of_device_id sprd_hwspinlock_of_match[] = {
	140	{ .compatible = "sprd,hwspinlock-r3p0", },
	141	{ /* sentinel */ }
	142	};
	143	MODULE_DEVICE_TABLE(of, sprd_hwspinlock_of_match);
	144
	145	static struct platform_driver sprd_hwspinlock_driver = {
	146	.probe = sprd_hwspinlock_probe,
d8c8bbbb BW	147	.driver = {
	148	.name = "sprd_hwspinlock",
	149	.of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
	150	},
	151	};
	152
	153	static int __init sprd_hwspinlock_init(void)
	154	{
	155	return platform_driver_register(&sprd_hwspinlock_driver);
	156	}
	157	postcore_initcall(sprd_hwspinlock_init);
	158
	159	static void __exit sprd_hwspinlock_exit(void)
	160	{
	161	platform_driver_unregister(&sprd_hwspinlock_driver);
	162	}
	163	module_exit(sprd_hwspinlock_exit);
	164
	165	MODULE_LICENSE("GPL v2");
	166	MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
	167	MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");
	168	MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");
	169	MODULE_AUTHOR("Long Cheng <aiden.cheng@spreadtrum.com>");